1. Field of the Invention
The present invention relates to the field of liquid crystal displaying, and in particular to a side-edge backlight module.
2. The Related Arts
Liquid crystal display (LCD) has a variety of advantages, such as thin device body, low power consumption, and being free of radiation, and is thus widely used. Most of the LCDs that are currently available in the market are backlighting LCDs, which comprise a liquid crystal display panel and a backlight module. The working principle of the liquid crystal display panel is that liquid crystal molecules are interposed between two parallel glass substrates and a plurality of vertical and horizontal fine electrical wires is arranged between the two glass substrates, whereby the liquid crystal molecules are controlled to change direction by application of electricity in order to refract light emitting from the backlight module for generating images. Since the liquid crystal display panel itself does not emit light, light must be provided by the backlight module in order to normally display images. Thus, the backlight module is one of the key components of an LCD. The backlight module can be classified as two types, namely side-edge backlight module and direct backlight module, according to the position where light gets incident. The direct backlight module arranges a light source, such as a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED) at the back side of the liquid crystal display panel to form a planar light source that directly provides lighting to the liquid crystal display panel. The side-edge backlight module arranges a backlight source of LED light bar at an edge of a back panel to be located rearward of one side of the liquid crystal display panel. The LED light bar emits light that enters a light guide plate through a light incident face of the light guide plate and is projected out through a light exit face of the light guide plate after being reflected and diffused to thereby transmit through an optic film assembly and form a planar light source the liquid crystal display panel.
The current market trend of the backlight module is bezel slimming. The attempt to use less LED lights while making a slim bezel would lead to an increasingly shortened distance between the LED lights and a light incidence surface of a light guide plate. And consequently, insufficient mixture of the lights emitting from the LED lights in the space results, making difference in illumination or color between two adjacent LED lights and generating the so-called “hot spot mura” (which means inhomogeneous brightness). For example, the slimmest bezel that is currently available in 4.9 mm and to effect homogeneous mixture of light between LED lights within such a slim range of the bezel would be a tough challenge.